Over the years, various drugs have been developed to assist in treatment of a wide variety of ailments and diseases. Various dosage forms for providing a release of drugs at a controlled release rate were also developed. There however remains an unfilled need for simple and reliable controlled release dosage forms that release active agents at predetermined times, predetermined release rates, and for predetermined duration, which dosage forms can be manufactured with relative ease and at an acceptable cost. Controlled release coatings, in particular prolonged release coatings are used to provide a specific release profile of the active contained in a core surrounded by such coatings. In order to ensure the target release profile the coating is prepared such that it provides the target release and that a rupture of the coating during the release is avoided. Typically the target release is achieved by including plasticizers and/or pore formers in the coating system to control drug diffusion through the coating.